1. Field of the Invention
This invention relates to a new and useful light transmitting and reflecting polarizer for use in liquid crystal display devices, which reflects and polarizes incident light, and diffuses and transmits light from a luminous body. More specifically, the present invention relates to a light transmitting and reflecting polarizer comprising a transparent or semi-transparent resin film, an adhesive layer having uniformly dispersed therein transparent and/or semi-transparent particles, and a polarizing layer, said layers being bonded to each other in this order.
2. Description of the Prior Art
Light transmitting and reflecting polarizers (simply referred to as polarizers herein) are used in liquid crystal display devices such as liquid crystal display devices for digital watches, electronic computers, and various meters and gauges.
Liquid crystal display devices are roughly classified into: (i) a type comprising a photoconducting member made of a material having high transparency, such as an acrylic resin plate having fine raised and depressed portions provided on the surface, a reflecting plate provided on the back surface of the photoconducting member, and a lamp provided to the side; and (ii) a type in which a reflecting material having the ability to permit light transmission is used instead of the photoconducting member and a luminous body comprising a fluorescent material and a radioactive material such as tritium (such that radiation generated in the radioactive material collides with the fluorescent material and emits light) is provided beneath the reflecting material. The polarizer of the present invention is used mainly in liquid crystal display devices of the latter type.
A known reflecting material having light transmitting ability is made by forming fine depressions and projections on the surface of a transparent synthetic resin film by treatments such as sanding or horning, and vacuum-depositing a metal film on the roughened surface of the resin film. However, when the amount of the metal deposited is limited in order to obtain sufficient light transmittance, the resulting film has inferior reflectance. On the other hand, as the amount of the metal deposited is increased, the light transmittance of the resulting metallized film decreases and becomes poor. Thus, it has been desired to overcome this difficulty.